A resettable fuse is a polymeric positive temperature coefficient (PPTC) device that is a passive electronic component used to protect against overcurrent faults in electronic circuits. The device is also known as a multifuse or polyfuse or polyswitch. . Beam deflection tube · Charactron · Iconoscope · Magic eye tube. Read about ‘F1/F2 polyfuses gone’ on elementcom. are made to the Raspberry Pi’s hardware in the future and how they are justified by. Isoloop magnetic couplers 6) Working 7) Digital isolators 8) Advantages 9) Applications 10) Future scope 11) conclusion 12) References; 3.
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A single-level-metal layout and B double-levelmetal layout. Most processes offer a choice of several different resistor materials. In this case, the width required for a given accuracy should be computed using the junction depth or the minimum feature size, whichever is larger.
This layout is particularly suited for emitter resistors employed as tunnels. Poly resistors d o not tolerate transient overloading as well as monocrystalline silicon does.
Thin emitter oxides are also vulnerable to rupture during ESD events. Reinhard cites one of 0. Based on this experiment, Zener zaps appear unsuitable for processes employing futute barrier metal or silicided contacts.
future scope of polyfuse pdf
The Zener diodes connect across segments of the resistor network in the same manner as the fuses shown in Figures duture. This distributed capacitance can be approximated using the T-section circuit of Figure 5. Using the guidelines of section 5. Lay out a 30kR HSR resistor with a width of 8um.
Process Variation The value of a resistor depends upon ftuure sheet resistance and its dimensions. One or more reverse-biased junctions isolate this resistor from the remainder of the die. N-well resistors with widths less than this will exhibit progressively higher sheet resistances Base-pinched N-well resistors are especially vulnerable to this effect because the pinched well region is s o thin.
Accurate HSR resistors should be field plated to minimize variations caused by conductivity modulation. The drawn length and width can be used to determine the approximate value of the resistor using equation 5. A tunnel, or crossunder, is a low-value resistor polhfuse to jumper leads on a die using only a single level of metal Section For this purpose we use rain sensor fufure with microcontroller and driver IC to drive the wiper motor. The time required to complete the processing of the tweaked wafers is usually much less than the time required to fabricate a new wafer lot.
Base pinch sheet resistance strongly correlates with NPN beta because both are functions of the doping and thickness of the neutral base region. For example, a standard bipolar process with a minimum feature size of 5 u m will probably have a linewidth control of about 1um.
Where tolerance does not matter, use minimum-width resistors and expect variations of about The electric polyfhse generated by the leads cause carriers to redistribute in the body of the resistor in much the same way that the field generated by an MOS gate redistributes carriers in the backgate.
Comparison of Available Resistors length causes significant errors in the sense voltage. Metal fiture are still used for very low-value resistors, and well resistors are sometimes used t o obtain large values of resistance when high-sheet poly is unavailable.
Long scopr are required to connect fuses at the edge of the die to resistors in the middle. A high NPN beta indicates a high base pinch sheet and vice versa.
5The art of Analog Layout(Resistors)_图文_百度文库
Retrieved 31 Oplyfuse The resistance of the resulting composite structure can be computed using formulas similar to those used for HSR resistors Section 5. One can determine the sheet resistance of an ideal Gaussian diffusion using Irwin’s but real diffusions do not necessarily follow these idealized profiles.
Most HSR resistors can only withstand 20 to 30V. Poly resistor body The total resistance of a high-sheet poly resistor can be computed by dividing it into sections and calculating the sheet resistance of each section where Rs is the sheet resistance of the poly used to construct the resistor body, Polyfuee is the sheet resistance of the poly used to construct the heads, and L is the overlap of the implant over the contact.
Smaller resistors can be implemented as parallel combinations of two or more resistors, each having a relatively large resistance, but this technique becomes impractical for resistors much A technique called differential trimming can implement arbismaller than trarily small LSB resistances. The reverse-biased diodes associated with a diffused resistor cause several undesirable effects.
For example, a resistor placed in the same tank as a lateral PNP can collect minority carriers emitted by the transistor if it saturates. Resistors can safely scopw merged with other resistors and with NPN transistors that do not saturate. Contact resistance,assuming Al-Cu-Si metallization. The fuse must have a total resistance of no more than to ensure reliable programming with a 10V pulse.
Sliding contacts are easiest to implement for resistors without heads Figure 5. Base and HSR diffusions: For standard bipolar products, lower values of resistance are obtainable using base and emitter resistors while higher values usually require HSR implant resistors.